Railway signaling device



A ril 18, 1939. R. A. TUOT RAILWAY S IGNALING DEVICE 3 SheetsSheet 1 Filed March 17, 1938 INVENTOR RAYMOND ARTHUR TuoT mm an ag, BY ATTYS.

April 1939- R. A. TU OT 2,154,877

- I RAILWAY SIGNALING'DEVICE:

Filed Ma frch 17, 1938 s Sheets-Sheet 3 BY WIWWM Patented Apr. E3 1939 warren sr-Arss iATENi'j ori ice caster; 'aamwar srsmrmc nnvrcn Raymond Arthur Tact,

' Strasbourg, France, as-

Application March 17,

1938, Serial No. 96,518

' In Switzerland April 21, 1937 1 3 Claims. (Cl. 246-67) Electric signaling devices for railways which do not-use any optical signalon the track and which comprise indicating or waming' apparatus in the drivers cabin of each locomotive and in the vicinity of the important points of the track such as level crossings, cross-overs, points, stations. and the like, are already kno I These apparatus are inserted'in a circuit which comprises the running track used as electric conductorand an insulated pilot conductor ari ranged along the track and with which one or more shoes carried by each locomotive come into contact, the locomotive carrying a direct current generator connected on the one hand to the shoes, and on the other. hand to earth.

The present invention relates to improvements in devices of this kind, making their use more general and permitting them in particular to be applied to electric traction railways.

on each locomotive a generator giving alternating currents '01 constant frequency.- The exciting members of this generator are supplied by 3 the trolleywire supplying'the traction current,

to obviate the necessity of a separate pilot conductor, connecting the actual apparatuses of the signaling device, that is to say, the generator and the indicators or warning devices of each machine, to one or more collecting slices of the lecomotive or of thetrain cooperating with the trolley wire by the intermediation of filtering ciravoiding the reception or" the traction can rent the signaling device and also a 31 less at s sling current into the tracticn m; mes.

2: the traction current is continuum, the filtering circuits may be simply constituted by a condenser accompanied if need by a self-insuction coil arranged in series and having a value su'itaoie to the frequency of the signaling cur- In the case of alternating current traction, the frequency of the "s ifierent from that of the tracti-or the filtering cells may comprise circa;

formed According to the invention, there is arranged.

of condensers and self-induction coils tuned to the frequency of the current to be blocked, allowing nevertheless the passage of the other-current which has-a different frequency.

To permit the dicators or warning devices of r 5 each locomotiv to take into account only the position of the track apparatus or of the other trains locatedin front and toavoid the said indicators or warning devices being influenced in an undesired manner by the track apparatus or those of the train behind, there may be used on the locomotive or the train a selecting bridge comprising iii-the main two collecting brushes cooperating with the trolley wire and adapted to be common with, those utilized for the traction current. With each collecting brush there starts a branch signaling circuit preferably through the intermediation of a transformer. These branch circuits terminate at a measuring apparatus or a. relay, of the diflerential type, so as only to be influenced when the current which it receives from the collecting brush located furthest in front on the trolley wire is greater than the mutant brought by the collecting brush located at the back. i

The signaling circuit may also comprise a commutator functioning preferably with a rhythm proportional to the speed of the locomotive. This commutator isarranged so as to place the gen"- erator of the locomotive periodically out of the signaling circuit and to substitute for it a direct electric connection (for the signaling frequency) between the trolley wire and. the running rail.

An example of the device according to the invention applied to an electric traction railway for monophase alternating current is shown by way of example in the annexed drawings, in which: f

Figure l is a simplified diagram of the signailing device ci a locomotive and a track apparatus;

Figure 2 more complete diagram of the equipment 3 iilustrates the connections ci a track apparatus for giving a warning and locking a level crossing barrier; 7

Train locomotives run on the rails it and the left-hand side Figure 1 shows in a very simplified manner the essential parts of the signaling equipmeat of a locomotive. V

The metallic mass cf iecomotive is represented the wheels 52 resting on the rails and :38 represent the two brushes coopereating with a ccntact rail ii a d these two brush-es one are separated as much as,possible from each other leaving between them a portion I93 of the rail.

There is located on the locomotive an alternating current generator l5 of different frequency from 'the frequency of the traction current.

This generator may be designed as an alternator rotated'by a motor l6 taking-its supply from a source of electricity |1 through conductors l8 and I9.

The exciting member indicated by 20 of the generator I5 is supplied through conductors 2| and 22 by a continuous current dynamo 23.

The field winding 24 of the dynamo 23 is supplied in a constant manner by the source of current l6 through conductors 25 and 26.

The dynamo armature 23 is set in rotation by.

the wheels |2 of the locomotive, so that the electromotive force of the dynamo 23 and consequently the field current of the generator |5 are proportional 'to the speed of travel of the locomotive.

The terminals'ofthe generator l5 are connected by conductors 21 and 28 to the primary 29 of a transformer the secondary 39. of which is connected by a conductor 3| to the wheels l2 of the locomotive and by a conductor32 to a filtering circuit constituted by a condenser 33 and selfinduction coil 34, connected in parallel.

The respective values of the capacity of the condenser 33 and of the self-induction of the coil 34 are arranged so as to obtain the condition of resonance for the frequency of the traction current and thus constitute a filter preventing the. passage of this current.

As the frequency of the signaling current produced by the generator I5 is made different from that of the traction current, the signaling current is not blocked by the filter 33, 34.

On the other side of the filter 33, 34, is arranged va conductor 35 which terminates at 36 in two branch circuits; one 31 comprising the primary 38 of the transformer and terminating at the brush l3, whilst the other branch 39 comprises the primary 40 of another transformer and terminates at the brush H.

The secondary 4| of the first transformer is connected by conductors 42 and 43 to one of the coils 44 of a differential galvanometer 45. In the same way, the secondary 45 of the other transformer is connected by conductors 41 and 48 to the other winding 49 of the galvanometer 45.

The movable member 56 of the galvanometer 45 is a current conductor angAis connected by a conductor 5| to one of the ter 'nals of the source l1.

In cooperation with the movable member 50, the differential g'alvanometer 45 comprises two contact pieces 52 and 53 which are connected by conductors 54 and 55 to indicators or warning devices 55 and 51 which are furthermore connected by a common conductor 58 to the other pole of the source l1.

The locomotive being supposed as travelling on the rails ID in the direction of the arrow, the right-hand portion of Figure l is in front of the locomotive.

It is supposed that on this right-hand portion there is an important point of the track, for example, a station, and that it is necessary for the approach of a train to be. signaled a certain time,

which is constant, before the passage of the train.

at the point under consideration of the track.

'At this point the trolley wire II is connected by a conductor 59 to a filter circuit composed of a condenser 60 and a self-induction coll 5| connected in parallel and having values so arranged as to fulfil the condition of resonance for the frequency of the traction. current.

The outlet terminal of the filter 55-5| is connected to the rails III by aconductor 52, a selfinduction coil 53 and a conductor 54.

There is also interposed on the trolley wirecoil 55 is accompanied by a condenser 59 so as to effect resonance for the signaling current.

The coil 63 is inductively coupled with a secondary winding 66 interposed in a circuit-which comprises a conductor 19, a contact piece 1| for a commutator or switch 12, a conductor 13, a galvanometer 14 and a conductor 15.

Similarly the coil 65 is inductively coupled with a secondary winding 68 inserted in a circuit which comprises a conductor 15, a contact piece 11 for the commutator 12, the conductor 13, the galvanometer 14, the conductor 15, a conductor 18, a filtering circuitrconstituted by a condenser 19, and a self-induction coil 85, arranged in parallel and the circuit is closed on to the secondary 68 by a conductor 8|.

The respective values of the co ndenser 19 and of the self-induction coil 89 are fixed in such manner as to fulfil the condition of resonance for the frequencyof the traction current, due to which no current of this frequency can fiow in the circuit of the secondary 68,

Obviously, when the circuit of a secondary winding 66 or 68 is closed, the self-induction proper of the coil 53 or 55 corresponding thereto becomes very slight and this coil does not con-. stitute with its condenser 61 or 59, a filtering circuit; the signaling current can then circulate freely in the coil 63 or 55. a

The movable member 82 of the galvanometer 14 is conductive and cooperates with a contact piece 83 suitably located. These parts 82 and 83' are interposed in an auxiliary circuit which comprises the following members: A source of 'electricity 85, a conductor 85, a warning device 85, a

conductor 81, a relay winding 88, a conductor 89,

the contact piece 83, the movable member 82, a conductor 9|], a relay winding 9| and a conductor 92 terminating at the source 54.

The movable armature 93 of the relay winding 88 is connected to the commutator 12, which is, I

on the other hand, brought back by a weight 94. The movable armature 95 of the relay winding 9| is connected by a conductor 96 to the conductor 89, and on the other hand this movable armatur cooperates with a contact piece v81 which is directly connected to the conductor 90.

Finally,-qn the running rails l9 there are provided insulatedsections respectively indicated by 98 and 99; which are connected by conductors I 00 and IM to the conductors and 92. An

electric connection ||l2 is established on' the run-- rging rails ID on each side of the sections 98 and The operation of the simplified device described above is as follows: 3

When the locomotive runs on the rails W, the dynamo 23 driven by the wheels produces an electromotive force proportional to the speed of the locomotive and owing to the conductors 2| and eraser"? quency but of a value proportional to the speed to of the locomotive.

The generator I supplies, through the conductors 21 and 28, the primary 29 of a transformer the secondary 30 of which is inserted in the following circuit:

Secondary 30, conductor 32, filter circuit 33, 34 conductor 35, and from the junction point 36 the circuit is divided into two branches.

first branch-Conductor 38, primary of the transformer '40, brush I4, portion "3 of the g0 trolley wire II.

Second branch-Conductor 31, primary 38 of the transformer, brush II, trolley wire. I I.

To the right of the following track apparatus the circuit is completed as follows:

6|, conductor 82, self-Induction coil 83, conductor 8.4, rails I0, wheels I2 01 the locomotive, conductor 3| and secondary ll.

The value of the current supplied by the secondary 30 depends, on the one hand, upon. the

electromotive force of the generator I5, and, on

current depends upon the speed of the loco-.

motive and the distance between this locomotive an the track apparatus.

other words, this current will be all the greater the greater the speed of the locomotive and the-'nearer this locomotive is to the track apparatus.

Where the track apparatus is in front of the locomotive as it is supposed in Figure 1, the cur rent does not divide exactly into two equal parts sbetween the two branches 31 and dealt with Trolley wire I I, conductor 59, filter circuit 60,

Thus, the passage of this current causes in the secondary 66 a certain electromotive force which, consequently is itself also proportional to the speed of the locomotive and inversely proportional to thedistance away of this.

This electromotive i'orce produces a current in the following circuit:

$econdary t6, conductor ill, contact piece it,

.switch or commutator l2, conductor l3, galvanometer l4, conductor l5 and secondary 56.

Thus, the movable member 82 of the galvanometer l4 deflects and when the locomotive is sufliciently near, the current has become such that this member t2 comes in contact with the terminai'piece and the following circult'is then closed:

Source of current tid, conductor 85, warning device 8%, conductor ill, windingda, conductor 89, contact piece 83, movable member 82, conductor 90, winding 9|, conductor 92 and source of current 8.4.

The alarm 86 operates which shows the attendant that a train is .about to arrive.

Furthermore, the winding 9| is excited. and attracts the armature 95, which producesfowing to the conductor 96 and contact piece 91, aper-- manent short-circuit between the conductors I9 and Bl.

Thus, if the movable member ,82 then leaves the contact piece 83, the preceding circuit neverth'el'ess remains closed.

Finally, owing to the closing of this circuit, the winding 88 is excited and attracts the armature 85 which brings the change-over switch 12 into contact with the terminal 11.

The circuit in which is the secondarywinding coefiicient of self-induction and as this coil is connected in parallel to the condenser 61 it iorms with it an absolute block to the signaling curcommutator I2, conductor I3, galvanometer I4,

conductor I5, filter circuit "40, conductor 8| and secondary 68.

This circuit being closed, the col 65' becomes "6 is then opened, the coil 63 h'asnow a normal very low in its coeflicient of self-induction, and

above. Actually the first branch comprises the I portion IM-of the trolley wire, and its impedance is greater than the impedance of the other branch. The result is that the primary is excited less than the primary 38, which causes a differ 53 ential eflfect on the member 50.

galvanometer is impelled to a greater extent towards the contact piece 53 and this all the more the greater the speed of the locomotive and the tab When the current produced by the generator 5% attains the maximum value to which the. de-

vice is'adjusted, the movable member comes into contact with the terminal 53 and the followa ing circuit is closed:

Current source il, conductor 5i, movable memher 58, contact piece 53, conductor 55, indicator 57, conductor Sland source of current 52.

The driver of the locomotive is then advised of the presene in front of him of a track apparatus in the closed position.

The current produced. by the generator E5 of the locomotive thus circulates as stated above, in the self-induction coil .63 of the track appags ratus.

Consequently, the movable member of the.

nearer this locomotive is to the track apparatus.

the condition of resonance is no longer fulfilled with respect to the condenser 69. Thus, the signaling current which is blocked by the circuit 63, B'I/can pass freely into the following section II of the trolley wire.

This section I I obviously terminates at a following track apparatus and the result'is that the resulting impedance oi the circuit into which passes the secondary to of the locomotive increases to a point such that the signaling current becomes relatively ieelole and the indicator 51 does not give any warning to the locomotive driver adapted to cause him to reduce thespeed.

During this time the alarm 8% functions con= tinuously, but when the wheels it? of the locomotive come to the right of the rail sections 98 and 95 these sections are connected electrically in such manner that a tine short-circuit is, produced,

through the intermediary of the conductors M0 and tilt, at the terminals of the winding 99.

This winding Si! no longer receiving current, the armature 95 leavesthe contact 9'? cutting out the alarm circuit 35 and the winding The alarm ceases to function and, under the action of the weight the change-over switch l2 returns to its initial position shown on Figure 1, after which the circuit into which the secondary eventually feeds is closed. I I

In this position, the secondary circuit 68 being open, the self-induction coil 65 and the condenser 33 act as a stopper circuit for thesignaling current. ,On the other hand, the coil 33 now only possesses a feeble coefficient of self-induction in such manner that the whole signaling current passes through the conductor 54. Thus the track apparatus is in the'initial position ready to take the following locomotive. I r

The locomotive which has just passed the track apparatus cannot be influenced by this return into an effective condition of the track apparatus, and this for the reason of the presence of the stopper circuit 65, 69, but even if this'circuit did not exist the equipment of the locomotive is such that there is no risk of the locomotive being obliged to slow down for any position what-- ever of a track apparatus which it has justpassed.

Actually in this case the current would be directed towards the rear part of the locomotive so that the portion I03 of the trolley wire would be traversed by the current which supplies the primary 33 and this current would be less than that of the primary 4I. Consequently, the movable member 50 of the differential galvanometer 45 would not be urged towards the contact piece 53 and the driver of the locomotive has not to reduce speed. I e

When the current in the circuit becomes zero, the member 50 comes into contact with the contact piece 52 which closes the following circuit:

Current-source I1, conductor 5I, member 50,

contact piece 52, conductor 54, indicator 56, conductor 58 and current source I1.

Thus, when thesignaling circ t is interrupted by accident or when there is in front of the locomotive another locomotive running strictly at the same speed, the indicator 53 functions and .the locomotive driver is warned.

The equipment of the locomotive and of the track apparatus shown on Figure 1 and described above, is simplified particularly and Figures 2 and 3 show a more complete representation of the normal equipment respectively of a locomotive and of atrack apparatus, for example, of

a level crossing with movable barriers. 9

on Figure 2, the rails are shown by I0, the trolley wire by II, the locomotive wheels by I2, and the collecting'brushes by I3 and I4. Between these brushes there is now shown the collection of the traction current comprising after the brush I3, a self-induction coil I04 and a condenser I05, arranged so as to form a stopper circuit for the signaling current. In the same. way, a similar stopper circuit I06, I0'I, is connected to the brush I4.

The two stopper circuits are conn ted by a conductor I03 which terminate a cond ctor I05 coming from the traction machine and a conductor IIO coming from the primary III of an auxiliary transformer connected by a conductor II2 to the wheels I2 of the locomotive.

The secondary II3 of this transformer feeds by means of conductors I I4 and H5 and through a switch II6, the motor I6 which produces the rotation of the generator I5 of the signalingv by these locomotives will always be in phase agreement.

The motor I3 also drives a continuous current dynamo. III called the exciter. This dynamo is intended to produce the current necessary not only for the excitation of the motor I6 and of the tachometrical dynamo 23 but also for the control apparatus and the warning indicators. The dynamo I I! thus plays the part of the source II' described with respect to Figure 1.

To this end, the terminals of the dynamo III are connected respectively by conductors II! and 9 to twobus bars I and -I2I .to which are attached all the conductors of the apparatus using the continuous current of dynamo III.

In the same way as on is connected to a circuit branch 3'! comprising a transformer 38, 4| and cooperating with the brush I4 is the circuit branch 39 and the trans-. former 40, 48.

The secondaries H and 46 of these transformers are connected as previously to the differential windings 44, 49 of a galvanometer 45 through conductors 42, 43 and 41, 48 respectively.

As previously, the branch circuits 31' and 38 terminate at a conductor 35 which through a filter circuit 33, 34, passes through a conductor 32 terminating at the secondary of a transformer. A conductor 3| connects the other terminal of this secondary to the wheels I2 of the loco motive. I

Nevertheless, the primary 29 of this transformer is connected directly by a conductor 21 Figure '1, the-brush I3 sic nently, through a conductor I26 to the conductor 21!. Thus, when the movable brush I23 is in contact with the contact piece I24, the primary 29 of the transformer is short-circuited.

' The fixed contact piece I25, also extending over a little "less than half a revolution, is connected to the generator I5 by a conductor I21, the movable armature 123 of a relay I 29, a conductor'l30 and a switch 254..

Therelay l23comprises another armature I38 interposed in a conductor I3I which connects the conductor I22 to the conductor 21.

The armatures I28 and I33 are integraL'so that only one at a time is in theclosed position.

The relay I29 is connected on one hand by a conductor I32 to the bus bar I20, and on the other hand by a conductor I33, a switch I34 and a conductor I35 to the bus bar I2I.

As previously, the exciting member 20 of the generator I5 is normally supplied by a tachometrical dynamo 23 driven by the wheels I2 of the I locomotive. This tachometrical dynamo is itself excited by a winding 24 connected by conductors 25 and 26 to the bus bars 525 and I21.

Nevertheless, one of the terminals of the exciting member 23 is connected permanently through a conductor I31 to the bus bar I20 and the other terminal leads to a change over switch areas? Furthermore, the movable member 3% of the switch I38 is acted upon to connect, according to its position, this terminal of the exciting member 20 either to the tachometrical dynamo 25 or to the bus bar I2I, that is dynamo I I1.

The movable member I45 of this switch is controlled by a relay I of which one terminal is connected by a conductor I42 to the bus bar I2l and the other terminal by a conductor I63 to a switch I44 itself connected by a conductor I45 to the bus bar I2I.

In shunt between the conductors I21 and 21, that is to say, in shunt on the terminals of the signaling current generator I5, are connected through the conductorslfl, I58 and I69 a voltmeter I and a of the difierential relay I1Iarrangedinseries.

The other winding I12 of the difiei'ential relay is supplied through conductors I13 and I14 by to say, to the exciter an electric tachometer I15 driven by the wheels I2 0! the locomotive.

The movable armature I16 of the diiierential relay MI, I12 controls the opening or the closing of a circuit comprising the bus bar I20, 9. conductor I11, an indicator or alarm I18, a conductor I19, the armature I16 a conductor I80 and a bus bar I2I 4 The movable member I8I of the voltmeter I10 is conductive and cooperates with a fixed contact piece I82, connected to the bus bar I2I by a conductor I82, whilst the movable member I8I is connected by a conductor I84 to an alarm indicator I85 connected by a conductor I85 to the bus bar I25.

The galvanometer 45 comprises a holding electromagnet I45 having *a fixed core 253 is connected on the one hand by a conductor I41 to the bus bar I and, on the other hand, to a. conductor I48 coming from the movable member 50 of the galvanometer. The conductor I 48 terminates at a fixed contact piece I49 with which cooperates a brush I511 integral withthe brush I described above.

The brush I55 is adapted in its passageto place in short-circuit the contact piece I49 with a contact piece ISI connected by a-conductor I52 to thebusbar I2I. r

The contact pieces I49 and I5I extend over approzdmately half a revolution and are arranged in such manner as to be placed in short-circuit by'thebrush I55 during the w ole time in which the brush I23is in contact m the contact piece lid,

As previously, the movable member 59 of the galvanometer is conductive and is adapted to iii) come into contact in the course of its deflection with fixed contact pieces 52 and 53. The fixed contact piece 52 presumed as located in the vicinity of the origin of the travel of the movable member is connected by a. conductor I Site a winding of the relay I54 which is connected by a conductor I55 to the bus bar IN.

The armature I55 of the relay I54 controls the opening or the closing of a circuit .omprising the busbar I20, a conductor I51, the indicator or alarm 156, a'conduc'tor I58 the armature I55, a condnctorfifl, and the bus bar I2I. I

The contact piece 53, arranged in the vicinity of the maximum deflection of the movable morn--v ber 50, is connected by a. conductor Hill to a winding ofthe relay I5I connected by a conductor I52 to the bus bar I25.

contact withthe fixed contact piece I24,

doctor its, the indicator or alarm 51, a conduc-- tor I55, the armature its, a conductor I58 and the bus bar I2I.

The difierentlal gaivanometer 45 comprises a third contact piece It? adapted to be contacted by the movable member 55 just at the end of its deflection travel. The contact piece I8! is connected'by a conductor I88 to a relay winding I55, itself connected by a conductor ISO to the bus bar I26. r

The movable armature IQI of the relay I88 Is inserted in a circuit which comprises a conductor I 92, an indicator-or alarm. I93, a conductor 252, the movable armature ISI, a conductor I9 1 and the bus bar I2I.

Generally, the members which have just been described operate essentially as has been described with respect to Figure 1; nevertheless, the equipment is actually completed by a certain number of auxiliary devices the role of which be explained hereafter.

- When the locomotive is running, the rotating commutator I23-I50 operates at a cadence proportional to the speed of the locomotive. When the brush I23 is in contact with the contact piece I25, the primary 251s placed in communication by the conductors 21, I22, I21 and I30 with the signaling current generator I5 in such manner that a certain signaling current is sent by the locomotive towards the followingtrack apparatus. The galvanometer 45 is influenced more strongly the greater the speed or the locomotive, and the nearer it is to the obstacle.

When the brush I23 of the commutator is in the primary 29 is short-circuited and consequently the impedance of the secondary 30 becomes zero. Thus, it behind the locomotive there is another approaching locomotive, the signaling current produced by this locomotive and received by its indicator or alarm apparatus will be inversely proportional to the space between the two loconiotives and no dangerous approachcan take p ace.

Furthermore, during the same period, the brush I55 places in short-circuit the fixed contact pieces I49 and MI so that by means of the conductors I47, Ito and I52, the circuit of the electromagnet. I to. of the galvanometer 45 is closed and the magnetic field produced by this electromagnet causes the movable member 59 to remain stationary in the position which it occupied when the brush I223 was in contact piece I25.

Due to this arrangement, the movable member 59, in so far as it is restrained inits movement of return to zero, occupies a position corresponding to the maximum value of the current even if the period oveswhich the maximum lasts is very short. a When another locomotive or a closed track apparatus is in front on the track at a definite distance according to the speed of the locomotive, the movable member 59 of the galvanometer, 45 is thus arrested on the contact piece 53: The fol= lowing circuit is then closed:

Bus bar I2I, conductor I52, fixed contact pieces I5I and I 49, brush rec, conductor I48, movable member 50, contact piece 53, conductor I55, winding IBI, conductor I52 and bus bar I25.

Hie winding I5I is then excited and attracts the armaturelfl which opens the following circuit:

The result is that the indicator 51 is no longer supplied and: the driver of the locomotive is thus advised that there is an obstacle in front of him and that its distance is such that the locomotive must be slackened in speed andstopped if -necessary.

If one of the circuit branches 31 or 39 were opened, the deflection of the movable member 50 would be a maximum. It would touch the contact piece I81 which would release the operation of the alarm, I93.

As regards the indicator 56, this obviously functions under the same conditions as described in connection with Figure l.

,On the example shown, it has been supposed that the ,indicators 56 and 51 are operated by opening the circuit and that the alarm I93 is operated by clodng the circuit, but it is evident that this is not obligatory andthat the types of relays may be diilferent'from those shown.

It, for any reason, the alternating current generator I does not work properly, the electromotive force which it produces is no longer in relation with that of the electric tachometer I15.

' The result is that the magnetic effects of the such a position that the locomotive can continue windings Ill and I12 on the armature I16 are no longer in equilibrium and the armature I16 closes the circuit comprising the indicator T18 and the conductors I11, I19 and I89. Thus the. indicator I18 operates and warns the driver.

If even the electromotive force of the generator I5 becomes zero, the movable member I8I of the voltmeter I19 would return to zero and, by touching the contact piecel82, it would close the;

circuit comprising the indicator I85 and the con-' ductors I83, I84 and I86 so that the driver would be advised of this occurrence. Y 7

This arises if an accident occurs to the tachometric dynamo 23 or again if the locomotive is stationary. 'In both cases, the driver operates the switch I44 which has for efiect to close the circuit comprising the conductors I42, I43 and I45 and the winding I4l.

The movable armature I49 is displaced and by 'the play of the commutator I38, the exciting member 29 of the alternator is separated from the tachometric dynamo 23 and connected by the" conductors I31 and I39 to the bus bars I26 and- I2I.

Thus, the excitation of the generator I5 becomes constant and the signaling circuit remains supplied with a potential which is reduced but is sumcient for the driver to be advised when the track apparatus or the train in frontare in the locomotive can start.

dynamo 23 is outof action,

its course at a reand without If the tachometric duced speed, signaling its approach risking accidents.

when the driver acts circuit comprising the .closed:. Bus bar I2l, conductor I32, winding I29, conductor I33, switch I34, conductor I35, bus bar The winding I29 is excitedand moves its armature I28, I33. The part I28 leaves its contact pieces and the part I36 moves on to its contact pieces. The result is that the circuit supplied by-the signaling upon the switch I34, the following members is current generator I5 is opened, whilst the primary 29 is short-circuited by the conductor I22,

the armature I36, the conductor III and the conductor 21.

Thus, the locomotive acts as a permanent short-circuit between the trolley wire II and the running rails I0 except obviously for the traction current the passage of which is prevented by the filter 33, 34.

' This manipulation of-the switch I34 by the driver has for its object to find out whether the obstacle, the presence of which on the track has brought'the movable member 59 of the galvanometer 45 on to the fixed contact piece 53,- is a running train or a track apparatus.

Actually in the first case, current circulates in the signaling circuit and the movable member 59 of the galvanometer 45 retains a deflection which is not zero.

in the second case, no current generator acts in the circuit and the movable member of the differential galvanometer 45 comes into contact with the contact piece 52, which closes the following circuit: 7 Bus bar l2l, conductor I52, contact pieces I49, I5I conductor I48, movable member 5ll,contact piece 52, conductor I53, winding I54, conductor- I55 and bus bar Y The winding I54 is then excitedand attracts I the armature I56 which breaks the electric connection between the conductors I58 and I59 and causes the operation of the indicator 56.

, Thus advised, the driver again opens the switch I38 and continues running taking into account the situation which has been discovered.

Figure 3 shows the diagram of a track apparatus with a device for signaling and the locking of a level-crossing barrier, the manipulating lever of which is shown by I95.

On this figure, there is furthermore seen a certain number of members already described for the simplified track apparatus shown in Figure 1. In particular the running rails Ill, the trolley line II with its extension II towards the following track apparatus.

As previously, the trolley line -I I is connected to the running rails III by the following members:

Conductor 59, filter tuned to the traction current fill-6|, conductor 62, self-induction coil 63 and'conductor 64.

The coil 63 co-operates on the one hand with a condenser 61 so as to form a filter tuned to the frequency of the signaling current and, on the other hand, with a secondary 66 in such a manner as to form a kind of transformer.

In the same way, there is interposed between the parts II and II of the trolley line, a self:--

induction coil 65 co-operating with a condenser 69 and a secondary 68 under the same conditions as those shown above with respecttothe coil 63, the condenser 6 and the secondary 66.

As previously, th secondary 68 acts in the circuit comprising a conductor 16, contact pieces ,11, co-operating with a change-over switch 12,

a conductor 13, the winding of a galvanometer 14, a conductor 15, a filter 19, 80 tuned to the frequency of the traction current, and a conductor 8|.

The secondary 66 is inserted in a circuit which comprises a conductor 18, contact pieces II, the change-over switch 12, the conductor 13, the winding of the galvanometer 14, the conductor 15, the filter 19,80, the conductor 8| and a conductor I96.

It is easy to see thataccording to the position of the change-over switch '12, it will be one or on the galvanometer winding '32. I

' current 94.

The movable member d2 of this galvanometer is a current conductor and is permanently con nected by a conductor 9? to one of the poles of a source of current 99.

The movable member 92 co-operates with three contact pieces indicated respectively by 898, I99 and 29%. The contact piece I98 has a very small angular extent and is arranged to be contacted by the movable member 82 when the latteris in the vicinitylof its zero deflection.

When the member 82 is in contact with the contact piece I99, the following circuit is closed:

Source of current 94, conductor I91, movable member 92, contact piece I99, conductor 29I, relay winding 26?, conductor 293 and source of When the movable member 92 of the galvanometer is in contact with the the following circuit is closed:

Current source 94, conductor I91, movable member 92, contact piece I99, conductor 294, relay winding 295, conductor 208 and 293, current source 84!.

The contact piece I99 has a considerable angular extent, so that it is contacted by the moving member 82 when the latter has reached approximately one-half its deflection and the contact between the contact piece I99 and the moving member 92 is maintained up to the full extent of its deflection.

The contact piece 299 however itself alsopossesses a considerable angular extent and the moving member 92 is arranged to be able to come into contact both with the two contact pieces I99 and too over the whole extent of this latter contact piece. When the moving member 82 has reached the contact piece 299, the following circuit is closed:

Current source 94, conductor l 91, moving member 22, contact piece 299, conductor 2931, relay winding 208, conductors 299 and 293, and current source cs. 1

The movable armature 2 iii of the relay 292 and an element 2H of the movable armature of the relay 2%, are inserted in the following circuit:

Source of current '84, conductor lB'I, conductor '232, armature Mil, conductor 293, armature 2-HT conductors 35, 255 and M3, relay winding 2M, conductor 2m, alarm 89, conductors 2I9 and 2%, current source 9d. 4 p

The relay winding 2!? acts on the same armature and in the some sense as the winding 295,

that is to say, that when this winding M? is ex cited, the armature Eli remains in the closed position even if the winding 295 ceases to he integral with excited.

mother armature element 229 is the element 2H and is inserted in the iollowing circuit:

Current source 88, conductors I91 rind 222, armature 229, conductor 222, relay winding 223, conductor 22 3, contact pieces 225 and 229ccoperating with an armature 221, conductors 228 and 299, current source (it. In arallel to the armature no there is provided the following branch between the conductor. is? and the conductor 222.

Between the conductors 2|5 and 203 is inserted the following branch:

contact piece I99, l

Conductor i229, hand switch 29% andconductor may winding 235 and'conductor 236.

Between the conductors 2th and 294, is also arrangedthe following branch:

- Conductor 23?, armature 23d of the relay 223 and conductor 239.

As regards the armature 2% of the relay 298, this is inserted in the following circuit:

Current source 9d, conductors I91 and H2, armature 2w, conductor 2I8, armature 2! i, condoctors 2M and ZIE, armature 249, conductor 2, relay winding 242, co-operating with the armature 22?, conductors 253 and 203, current source 95 'lhe marine m is integral with a bolt :44

co-operating with a notch 249 provided in a disk.

2136 connected by acrank arm 24'! to the armature 299 of the ,-relay 222. I

The armature 239 is also integral with a bolt 249 co-operating with a notch' 249 provided in a sector 25%! integral with the manipulating lever I95.

As previously, there are provided on the running rails I0, two sections 01' insulated rails 99 and 99 connected respectively by conductors I00 and IIII to the conductors ZIB and; H9 situated on each side or the relay winding 211. A direct electric connection I92 Joins the rails I9 oneach side of the sections 98 and 99.

Finally, an ordinary cut-out switch I is located between the two sections II and II' 01' the trolley wire. when this switch 25I is closed, these sections II and H are directly connected and obviously no current can pass into the coil 85.

The parts being in the positicnshown by Figure by induction, the secondary 6i; feeds into itscircuit a current proportional to the signaling current and having the same frequency.

' The filter 79-99 tuned to the ii-action current does not constitute an obstacle to the passage of this secondary signalling current, so that the winding .ofthe galvanometer 72 is excited and the moving part at deflects.

As the locomotive approaches, the current progressively increases and the same applies to the deflection of the moving member 82.

This moving member first encounters the con- I tact piece 5 9'3, but the action which results there from'is, for the moment, of no importance.

' when theintensity or the current attains the value determined for causing the approach of the locomotive to he advised, the moving member comes into contact with the contact piece I99 which excites the relay 299 and displaces the double armature 2i i-iiit.

An electric connection is established between the conductors 219 and 286, so that the alarm 86 operates and at the same time the winding 2 It is excited and thus the armature 2H remains in the position which it occupies even it the movable member 92 left the contact piece I99, for example in the case of stoppage of the locomotive. At the same time, the branch 232, 235, 236 is traversed by a current so that the excited relay 235 simultaneously moves the armatures 233'and the change-over switch 12. i

As the armature 233 forms part of the exirequency oi the citing circuit of the winding 295, it immediately iirops and then, rises and this armature commences to oscillate as well as the change-over switch I2.

' The result is that the secondaries 8.8 and 58 are alternately placed in circuit with the galvanometer I4 and at the same cadence the signaling current will pass ei; er into the conductor 64 and the running ils I8 or into the section I I of the trolley wire up to the followin track apparatus.

It is due to these oscillations of the changeover switch I2 that the locomotive which approaches can signal its arrival to the track apparatus located beyond the one under consideration.

If the signaling current continues to increase owing to the approach of the locomotive, the movable member 82 reaches the contact piece 288. The relay winding 288 is excited, the armature 248 is attracted and an electric connection izsnestablished between the conductors 2l5 and The winding 242 is then excited and it displaces simultaneously the armature 221 and the bolt 244.

The disk 245 is freed and there are then two cases to be considered: 1st case: The level crossing barrier is open and the lever I95 is in the position shown on Figure 3.

' The bolt 248 rests on a smooth part of the sector 258 and the armature 238 of the relay 223 remains stationary in spite of being unlastened. :Thus the change-over switch I2 continues to escillate and the locomotive which has caused this operation is forced to stop, since the signaling current pases through the direct connection 84 and increases more and more. 2nd case: The level crossing barrier is closed and the lever I95 is in the corresponding position, that is to say, that the notch 249 is under the bolt 248. t

- As the armature 238 has been liberated by the bolt 244, the bolt 248 drops into the notch 249 and consequently the lever I95 canno longer be manipulated, and it is impossible for anyone to accidentally open the level crossing barrier.

Furthermore, an electric connection is established. by the armature 238 between the conductors 231 and 239.

Y Thus in order to supply the relay winding 235, the current need no longer pass through the intermittent contact formed by the armature 233 and owing to the permanent operation of the relay 235 the change over switch 12 becomes stationary in the upper position according to which the secondary 6% is in circuit.

Thus the inductance between the sections II and II' of the trolley wire becomes very feeble and the signaling current is directed towards the following track apparatus.

The present track apparatus does not influence in any way the indicators of the locomotive and the latter can pass it without having to slow down. This is normal since the lever I95 is in the correct position and the barrier is 7 closed As soon as the locomotive passes the track apparatus, it clears the sections of insulated rails 98, ,89 and the wheels of the locomotive thus place the winding of the relay 2 I 'I in short-circuit through the conductors I88 and IN.

The double armature 2, 228 of this relay therefore drops so that in the first place the 7 electric connection is ensured between the con- 248 is raised, permitting the free control againoi. the barrier by means of the lever I85.

On rising, the bolt 248 causes the disc 245 to rotate and the notch 245 comes under the bolt As the relay 242 is not excited since the movable member 82 is no longer in contact with the contact piece 288, the bolt 244 drops immediately into the notch and fixes the disc 245. At the same time the armature 22'! leaves the contact pieces 225 and 226 and the relay 228 is'no longer excited, but the bolt 248 remains ilxed since it is itself held stationary by the bolt 244.

At the same time the armature element ,2 cuts off the electric connection between the conductors M3 and 2, thus the operation of the alarm 86 is interrupted and the relay 235 is no longer excited. The commutator I2 returns to its position of rest as shown in Figure 3.

The attendant can then open the level crossing barrier as the track apparatus has taken up its initial state and is ready to operate afresh.

If after having signaled its arrival, the train had stopped or had slowed down sufllcientiy, the movable member 82 would have dropped to thezero point of its deflection placing itself in passing in contact with a contact piece I98.

The relay 282 would have been immediately excited and thedisplaced armature 218 would have interrupted the electric connection between the conductors 2l2 and. 2I3. This closing would have caused, as previously, the stoppage of the exceptional circumstances even if a train is ap-' proaching. I

It is to be noted that when carrying out this, exceptional manipulation the attendant causes the exciting circuit of the relay 235 to be cut, since the armature 238 is raised and thus even if the train continues to approach, the changeover switch I2 remains stationary in the position of Figure 3 and the indicators of the locomotive warn the driver that the track apparatus must not be passed.

Obviously it would be easy ferent phases of operation of the apparatus where, instead of a barrier controlling a level crossing, it were a matter a: controlling a point.

In this case, the sector would have two notches to imagine the dife Actually, when the first locomotive passes on to the section of rails 94 and 08 and brings back all the members to the position of rest, the movable member 82 does not return to zero, since the following train produces a signaling current which is already considerable. It is therefore necessary that at this moment, whatever may be its position, the movable member 82 should be in contact with the contact piece I88 or even the contact piece I" in order to cause the members of the track apparatus to carry out the movement required by the approach of the train.

This condition is only fulfilled if, as in Figure 3, a considerable angular extension is given to the contact pieces I99 and 290.

It is obvious that what has been described for signaling on railways with alternating current electric traction, applies where the traction would be by continuous current or even by steam if a mixed circulation of electric and steam trains takes place over the track.

Similarly and without thereby departing from the general scope oi. the invention, there might be used as the generator I of constant frequency alternating current any type of suitable apparatus, such as an alternator, commutator, vibra-.

tor, generator by thermionic valves or the'like.

If in the example described above, it is presumed for the purpose of simplification that the galvanometers mounted on the locomotives made contacts and closed circuits, it is of course understood that in practice the apparatus might be so arranged that they cause, on the contrary, the opening of circuits normally established, this being in order to obtain a strict control of their operation.

I claim:

1. A signaling apparatus for electric railways employing the track rails as part of a signaling circuit, comprising an insulated conductor along the track, means on the trackfor establishing electrical connection between said rails and insulated conductor, collectors disposed on locomotives running on said track rails and making contact with said conductor, a signal indicating device, an alternating current generator 01' constant frequency for actuating the indicating device over said collectors, and a direct current dynamo supplying an electromotive force proportional to the locomotive speed, said dynamo energizing the field of said alternating current generator.

- 2. An apparatus according to claim 1, comprising further an electrical connection between the indicating device and the track rails, a twoway switch on each locomotive operated in rhythm with locomotive speed, said switch periodically the track for supplying traction current, an A. C.

signaling generator on each locomotive running on the track, a signal indicating device, brushes on said locomotive contacting the power line to supply signaling current to the latter, track devices including an electricalconnection between said rails and power line, and filters in said .con-

nection to separate the signaling current from the traction current, said filters including an induction coil having a secondary winding magnetically coupled thereto and so arranged in a circuit including the signal indicator that the induction coil alternatively functions as a filter element and as primary transformer winding when the circuit of the signa indicator is opened and closed.

RAYMOND ARTHUR, TUOT. 

